EFFECTIVENESS OF SECANG WOOD (Caesalpinia sappan l) CONCENTRATION AS NATURAL INDICATOR FOR ACIDIMETRY METHOD

Abstract

cidimetry is a titration method used to determine acidic levels such as H
2
SO
4,
ISBN: 978-602-5614-24-8 Page 245
 
3
 and HCl with methyl red                       
(MR)1% w/v as indicator. As synthetic indicator, MR is relatively expensive, therefore a replacement indicator is
needed. This study aimed to investigate the potential of a natural indicator from secang wood (Caesalpinia
sappan l) containing brazillin compounds to be used as replacement of MR. The efectiveness of wood
concentration 0.5; 1.0; 1.5 and  2 % w/v used as indicator of acidimetric titration, particularly for standardizing
HCl solution was measured. Next, the minimal concentration of wood secang which can be used as indicator of
acidimetric titration was determined. The result showed that secang wood has potential to be used as
replacement indicator of MR. The percentage difference of concentration of HCl solution using MR indicator
1.0% with wood concentration 0,5; 1.0; 1.5 and 2.0 % w/v were 6.7; 6.7; 10.0; and 21 % respectively. Minimum
concentration of wood secang that can be used as indicator in acidimetry is 0.5 %b/v.
Keywords: acidimetry, secang wood, natural indicator, and synthetic indicator MR